The invention relates to shelf units, and more particularly relates to light-duty shelf units. In its most immediate sense, the invention relates to inexpensive, light-duty all-plastic shelf units such as are sold in knocked-down form in mass market outlets.
Conventionally, a shelf unit of this type has a plurality of shelf modules. Each module has a joint at each corner. When the shelf unit is assembled, tubular vertical spacers must be fitted into corresponding joints of adjacent modules. As a result, a conventional shelf unit can only be assembled to form a vertical stack of shelves. This has little visual interest and does not allow the customer to customize the configuration of the shelf unit to meet his or her specific needs.
It would be advantageous to provide a shelf unit that would be more versatile and would have a more attractive appearance.
One object of the invention is to provide a shelf unit that would be more versatile and would also have a more attractive appearance.
Another object is, in general, to improve on known shelf units of this general type.
In accordance with the invention, a unitary all-plastic corner joint for a light-duty modular shelf unit is provided. The corner joint comprises a generally cylindrical housing having open top and bottom ends, a cylindrical central bore with a central stop region therein, an annular recess located inside the housing at the top end thereof concentric with and above the central bore, and an annular projection at the bottom end of the housing, the projection being dimensioned to mate with the recess.
With such a corner joint, shelf modules can either be interlocked directly (without using vertical spacers) or coupled together using vertical spacers. This makes it possible to build the shelf unit in customized and attractive configurations that meet the user's specific needs. Additionally, with such a corner joint, cost advantages are also brought about. This is because the vertical spacers that support the shelf modules in a stack can be cylindrical, and can be extruded rather than injection-molded. This substantially reduces the capital investment required to make the shelf unit.
In further accordance with the invention, a unitary all-plastic shelf module for a light-duty modular shelf unit is provided. The shelf module comprises at least one corner joint located at a corner and at least two peripheral pieces joined to the corner joint at the corner. Each joint has a generally cylindrical housing having open top and bottom ends located respectively above and below the peripheral pieces, a cylindrical central bore with a central stop region therein, an annular recess located inside the housing at the top end thereof concentric with and above the central bore, and an annular projection at the bottom end of the housing, the projection being dimensioned to mate with the recess. A shelf unit made from such a shelf module has the above identified advantages, and additionally has the advantage that each corner joint serves as a leg that supports the shelf unit above the floor, thereby making separate leg parts unnecessary and reducing manufacturing cost.
Although the shelf module can be of any shape (e.g. triangular, half-round, quarter-round), in accordance with the preferred embodiment the shelf module is rectangular. In such a case, there will be four peripheral pieces made up of two end pieces and two side pieces. If the shelf module is square, the end pieces and the side pieces will all be identical.